Users Guide
Border Gateway Protocol
BGP is an external gateway protocol that transmits interdomain routing information within and between autonomous systems (AS). BGP
version 4 (BGPv4) supports classless inter-domain routing (CIDR) and the aggregation of routes and AS paths. Basically, two routers
(called neighbors or peers) exchange information including full routing tables and periodically sent messages to update those routing
tables.
NOTE: For more information about configuring the border gateway protocol (BGP), see the
BGP
section in the
Dell
Networking OS Configuration Guide
.
Topics:
• BGP IPv4 Commands
• MBGP Commands
• BGP Extended Communities (RFC 4360)
• IPv6 BGP Commands
• IPv6 MBGP Commands
BGP IPv4 Commands
Border Gateway Protocol (BGP) is an external gateway protocol that transmits interdomain routing information within and between
Autonomous Systems (AS). BGP supports classless interdomain routing (CIDR) and the aggregation of routes and AS paths. Basically,
two routers (called neighbors or peers) exchange information including full routing tables and periodically send messages to update those
routing tables.
NOTE:
Dell Networking OS supports 2-byte (16-bit) and 4-byte (32-bit) format for autonomous system numbers
(ASNs), where the 2-byte format is 1 to 65535 and the 4-byte format is 1 to 4294967295.
NOTE: Dell Networking OS supports dotted format as well as the traditional plain format for AS numbers. The dot
format is displayed when using the show ip bgp commands. To determine the comparable dot format for an ASN from
a traditional format, use ASN/65536. ASN%65536. For more information about using the 2– or 4-byte format, refer to
the
Dell Networking OS Configuration Guide
.
address-family
Enable the IPv4 multicast or the IPv6 address family.
Syntax
address-family [ipv4 {multicast | vrf vrf-name} | ipv6 unicast [vrf vrf-name]]
Parameters
ipv4 multicast Enter the keyword ipv4 followed by the keyword multicast to enable BGPv4
multicast mode.
ipv4 vrf
vrf-name
Enter the keyword ipv4 followed by the keyword vrf and then the name of the VRF to
enable VRF mode.
NOTE: Use this attribute to start a BGP instance corresponding to either a
specific address family in a default VRF or an IPv4 address family in a non-
default VRF.
ipv6 unicast Enter the keyword ipv6 followed by the keyword unicast to enable BGPv6 mode.
vrf
vrf-name
(Optional) Enter the keyword vrf followed by the name of the VRF to install the IPv6
route in that VRF.
NOTE: It will not be possible to enable VRF mode for IPv6 unicast without
configuring the corresponding IPv4 unicast mode for the same VRF. While
10
308 Border Gateway Protocol